The amount of damage to the insulated layer on brain nerves, rather than the severity of the injury itself, may be the reason some young victims recover from brain trauma more quickly than others, according to new research by UCLA and USC scientists.
The study published in The Journal of Neuroscience on Wednesday may give insight into how athletes are affected by sports concussions, said Christopher Giza, professor of pediatrics and neurosurgery at the UCLA David Geffen School of Medicine and Mattel Children’s Hospital.
UCLA researchers also take part in a study on sports concussions under an NCAA and U.S. Department of Defense initiative, the CARE Consortium, which uses the same brain imaging.
The research shows that assessing the severity of damage to myelin, a fatty tissue that protects nerve signals as they travel across the brain, can help doctors better predict a patient’s recovery experience. The damaged myelin reduces the brain’s ability to transmit information signals and impedes the person’s ability to learn, Giza said.
Researchers found the severity of injury did not differ in patients with significant myelin damage versus those with little myelin damage, said Emily Dennis, an author of the study and a researcher at the USC Keck School of Medicine.
“While injury severity is certainly a strong predictor of outcome, we are learning that severity is not the whole story,” Dennis said. “Two kids with similar injury profiles can have different recovery experiences, and our study shows that examining several types of brain imaging measures together could help improve these predictions.”
The group of scientists assigned a series of mental tasks to 32 youths, aged 8 to 19. All had suffered a moderate to severe brain injury within the last five months. The tasks tested their processing speed, verbal learning, short-term memory and mental flexibility, according to a UCLA press release.
Scientists measured each person’s cerebral electrical activity during these tasks to measure how fast his or her nerve fibers transmitted information. They also took images of the brain to see how intact or how damaged the myelin was, the press release stated.
Half of the participants in the brain-injured group had widespread myelin damage, and the other half had little myelin damage. In the group of survivors, the severity of the initial brain injury did not predict who did well on the tasks and who did poorly, Giza said.
The results showed those with little myelin damage processed new information as rapidly as healthy kids. They were 9 percent more accurate on the tests than those with more myelin damage.
Researchers are now hoping to find differences in how concussions and mild traumatic injuries affect myelin, Giza said. Dennis added they also plan to analyze brain structure and function after injuries to predict long-term outcomes for children whose injuries affect them for several years.
Compiled by Jorge Valero, Bruin contributor.